DE102008010426B4 - IP-based communication method for mobile devices - Google Patents

Abstract

Method for integrating mobile radio devices (3, 3 ', 3' ') in IP-based data networks, wherein a. the mobile device (3, 3 ', 3' ') established via an authentication a data mobile connection via an access point to the provider, b. the mobile device (3, 3 ', 3' ') by an IP server (9, 9') based on the authentication data assigned a fixed IP address from the address space of its closed user group and the assignment is permanently stored, c. the data mobile connection is coupled with the IP-based data network via the gateway (10, 10 ') of the provider over the allocated IP address during the duration of the data mobile connection, wherein the gateway (10, 10') uses permanent routing bidirectional communication connection between the mobile device (3, 3 ', 3' ') and the IP-based data network within the address space of its closed user group, characterized in that d. in that the IP address assigned to the mobile radio device (3, 3 ', 3' ') is a private IP address from a private IP network segment of the provider, e. a client (1, 1 ') from a public IP-based network establishes an IP connection to a dial-in server (7, 7') of the provider with publicly accessible IP address by means of password-based authentication, f. the client (1, 1 ') assigned by the IP server (9, 9') of the provider on the basis of the authentication data another private IP address from the private IP network segment of the provider from the address space of the same closed user group and permanently stored the assignment will, g. the data mobile connection and the client (1, 1 ') are coupled from the public IP-based network based on the associated private IP addresses over the private IP network segment of the provider.

Description

1. Technical area:

The present invention relates to an IP-based communication method for mobile devices.

2. State of the art:

Due to increased bandwidth, good network availability and a significant decline in the price of connection costs in GSM mobile networks, there is a desire instead of just for the mere voice transmission and sending SMS messages also increasingly for data transmission between digital terminals from IP-based data networks (Internet , Intranets) and in particular for the automated exchange of information between terminals (M2M = "Machine to Machine" - communication) to use in different wired data and / or mobile networks. Desirable fields of application include the interrogation of traffic flow sensors within congestion detection systems and / or traffic control systems. Another desirable application is the monitoring and control of solar or wind power plants. The integration of the systems via GSM mobile networks has the advantage that at sites far away from wired telephone landline networks, a considerably lower installation costs to secure the accessibility of the system is required. Incidentally, due to the pricing in GSM mobile networks in packet-oriented data transmission (GPRS = "General Packet Radio System" and UMTS = "Universal Mobile Telecommunications System") over fixed network data transmission significant savings in connection costs possible.

Here, however, there is the problem that a data connection to a mobile terminal (cell phone or radio modem) can generally not be initiated from "outside". As a manifestation of this problem, a data connection to a mobile terminal can also be established non-initiatively from an external IP-based data network. Although the specifications for the GSM mobile radio standard with GPRS and UMTS generally also provide IP-based data transmission. Even if a mobile terminal via the next access point ("AP" = "Access Point") has established a mobile data connection, such as the GPRS protocol, to its provider (network operator) and "online", but can be from an external IP-based data network to the mobile terminal are not accessed by initiative, because the two remote sites are not in the same IP address space. While in the case of voice, SMS and modem connections (CSD, Circuit Switched Dialing) the communication partner knows the telephone number of the mobile subscriber line and can dial it from another device, with IP-based mobile radio connections the current IP address of the mobile terminal is not known. Thus, the mobile terminal is not identifiable from the outside, which is sufficient for "surfing" or retrieving e-mails with the mobile device, but an IP-based M2M communication is not possible. Finally, in the case of IP-based data connections, the accessibility of the mobile device by the network operator for the protection of users against unwanted data traffic or access from the Internet is generally limited or prevented by access restrictions, for example with the aid of firewalls.

In GPRS and / or UMTS networks, therefore, only connections are possible which are established by the mobile device to the public Internet and not vice versa. A system equipped with a mobile modem is not reachable by conventional means of connection from the Internet. The initiative execution of query and / or control functions from the Internet is therefore not possible. Also not possible are data connections between two mobile devices in the network of a provider with each other and between mobile devices in different networks of different providers (for example, T-Mobile and Vodafone).

To overcome this problem, the so-called "lock calling" was developed as a stopgap to enable the query of systems with mobile modems: The radio modem is called briefly and prompted to establish an Internet connection to the control center. Alternatively, the call can be made via SMS. This procedure is not only cumbersome, but above all also associated with high costs, since no standard components such as routers etc. can be used. Another method is to use your own M2M gateways. Here, the mobile terminal keeps itself permanently via a manufacturer-specific protocol the connection to a gateway computer in the control center and is thus always available. This procedure is cumbersome and involves high costs and is therefore not suitable for the mass market. Furthermore, both last-mentioned approaches have the disadvantage that they are proprietary solutions that require completely compatible connection technology on both sides of the communication link.

As a further feature of the illustrated problem, a GSM data connection to a mobile terminal can not be initiated by initiative from another mobile terminal.

The US Pat. No. 6,466,571 B1 discloses a method for locating a mobile device and transmitting an IP packet addressed thereto. That of the US 64 66 571 B1 proposed method provides a relatively complex process structure through the interposition of an additional localization server and requires for physical localization of the mobile device an additional communication sub-loop between home agent and authentication server on the one hand and home agent and the localization server on the other. The assignment of the IP address to the mobile device takes place after that of the US 64 66 571 B1 proposed solution manually in the mapping table of the authentication server by an IP network provider. As a result, no automatic selection, assignment and permanent storage of the IP address during the first dial-up of the mobile device is possible. In addition, in the dynamic allocation of static IP addresses, there is basically no permanence of the assignment. The IP address assigned to the mobile device must be re-communicated after each new dial-in for re-IP connection from the outside outside the automated procedure, so that an IP packet can be addressed to the mobile device.

The US Pat. No. 7,289,463 B2 discloses a hierarchical wireless network and associated method for delivering IP packets to mobile devices. A solution for the initiative establishment of an IP data connection to a mobile device from an IP-based data network out of the US Pat. No. 7,289,463 B2 not taught.

Perkins, C .: IP Mobility Support RFC 2002, Networking Group, Oct. 2002, pp. 1-79 deals with regulations for IP routing for mobile devices when moving through different IP-based data networks. A solution for initiating an IP data connection to a mobile from an IP-based data network is not taught by the publication.

3. Presentation of the invention:

The invention has for its object to be able to initiate a data connection to a mobile terminal (mobile or wireless modem) from "outside". In particular, mobile GSM terminals should be able to be integrated into IP-based data networks in such a way that a data connection to the mobile GSM terminal can be established by initiative from IP-based data networks.

According to the invention the object is achieved by the method described in claim 1. Advantageous embodiments are described in the subclaims.

• a. das Mobilfunkgerät über eine Authentifizierung eine Daten-Mobilfunkverbindung über einen Zugangspunkt zum Provider etabliert,
• b. dem Mobilfunkgerät durch einen IP-Server anhand der Authentifizierungsdaten eine feste IP-Adresse aus dem Addressraum seiner geschlossenen Benutzergruppe zugeordnet und die Zuordnung dauerhaft gespeichert wird,
• c. die Daten-Mobilfunkverbindung anhand der zugeordneten IP-Adresse über ein Gateway des Providers mit dem IP-basierten Datennetz während der Dauer der Daten-Mobilfunkverbindung gekoppelt wird, wobei das Gateway mittels Routingvorschriften eine dauerhafte bidirektionale Kommunikationsverbindung zwischen dem Mobilfunkgerät und dem IP-basierten Datennetz innerhalb des Adressraumes seiner geschlossenen Benutzergruppe vermittelt.

The core of the invention is according to claim 1, a method for the integration of mobile devices in IP-based data networks, which is characterized in that

• a. the mobile device establishes a data mobile connection via an access point to the provider via an authentication,
• b. the mobile device is assigned by an IP server on the basis of the authentication data a fixed IP address from the address space of its closed user group and the assignment is permanently stored,
• c. the data mobile connection is coupled with the IP-based data network during the duration of the data mobile connection by means of the assigned IP address via a gateway of the provider, whereby the gateway uses routing provisions to establish a permanent bidirectional communication connection between the mobile device and the IP-based data network of the address space of its closed user group.

Mobile device is any mobile device with a GSM mobile interface to understand, such as cell phones or other communication devices with mobile modem. Provider means the provider of the communication method according to the invention. Servers are generally programs that communicate with other programs, the clients, to provide them with access to specialized services. An IP server is accordingly a program that distributes IP addresses to clients in IP-based data networks. The proposed method has the advantage that due to the assignment of a fixed IP address from the address space of a closed user group, an IP-based data connection to the mobile device can be initiated by other subscribers of the same user group. By according to step a. established mobile data connection is always maintained ("always on"), the mobile device is in step b. assigned IP address always available. Within the closed user group, all devices can communicate with each other regardless of their actual physical connection. Since data connections in mobile radio networks (GPRS, UMTS) today are purely volume-based and not time-oriented billed, the constantly maintained data mobile connection ("always on") basically causes no cost as long as it is only kept available. Only in the case of communication accesses do connection costs arise depending on the data volume transferred. The resulting connection costs can be flat-rate for individual volumes ("flat rate"). To secure the communication connection, the mobile devices need no additional software because conventional data mobile connections (GPRS and UMTS) are already encrypted and secured. Only the access data of the access point (APN name = "Access Point Name") and the establishment of the connection according to step a. Required authentication data must be configured in the mobile device.

The assignment of the IP address according to step b. expediently takes place in time before the first connection, for example, when the contract between the user and provider together with the assignment of the user name and password. In this case, the IP address is already assigned to the user name before the first dial-in and stored permanently. In an alternative embodiment, the selection, assignment to the user name and permanent storage during the first dial-up of the mobile device according to done.

The formation of a closed user group is achieved simply by automatically assigning an IP address from a specific IP subnet within the provider's network. The address space of the closed user group corresponds in this case to the entire subnet from whose area the assigned IP address originated. An exact determination of the amount of IP addresses available in the subnet can be achieved by masking depending on the desired number of total users and thus be selected according to the respective requirements of the respective user. In an alternative embodiment, the various user groups managed by the provider can be isolated from one another via a firewall rule and / or routing rules even when public IP addresses are assigned and within subnets.

The authentication according to step a. can be easily controlled by the use of any dial-up server with verification of the dial-in remote site using typical authentication features. Preferably, for example, a RADIUS server (RADIUS = "Remote Authentication Dial-In User Service), which authenticates the identity of the remote station based on a particular user / password combination is suitable. A simplified form of authentication without the need for input of data can be achieved by checking an item containing the authentication data, such as a chip, RFID or magnetic stripe card with password safe or security key or a USB key with password safe or security key (token ).

In a particular embodiment, the mobile device is permanently assigned a public IP address. Public IP addresses are those that are routed to the Internet after the IANA (Internet Assigned Numbers Authority) has been established. This has the particular advantage that the mobile device is permanently accessible from all public IP networks, such as the Internet, without having to authenticate the remote stations for data exchange with the mobile device itself. In this case, the address space of the closed user group corresponds to the entire public Internet. A security of access to the mobile device can be achieved by a separate password protection on the mobile device itself or by an intermediate firewall.

In a modification of this embodiment, the provider assigns a public IP address several times to different mobile devices. The traffic between the different mobile devices with the same public IP address on the one hand and the respective clients communicating with them on the other hand is routed in each case depending on the public IP address of each client. D. h., There is a source-dependent address translation. A client in this sense can be any IP-network-capable terminal, ie personal computers, mobile phones, organizers, etc. In this method, the provider requires the public IP address of the requesting client for realizing the source-dependent address translation, which he notes in a conversion table , Alternatively, the client from the public IP-based data network for initial recording of the data connection as part of a logon process, the assignment of the IP address to the respective mobile device set, with his public IP address automatically entered into a conversion table and from this time this mobile device permanently assigned. This modification has the advantage that the provider generally requires fewer public IP addresses to integrate the mobile devices of its customers.

In a further embodiment, the mobile device is permanently assigned a private IP address from a private IP network area of the provider. Private IP addresses are those that are not routed to the Internet after the IANA (Internet Assigned Numbers Authority) has been established. The data connection with clients from the Internet is here established by the client also logs using password-based authentication via a dial-up server to the private IP network of the provider. Here, the client is permanently assigned and stored a private IP address from the address space of the closed user group of the mobile device. Both subscribers, both the mobile device and the respective client thus receive IP addresses from the address space of a closed user group within a private IP network area of the provider. This ensures that only participants from a closed user group can communicate with each other. This method has the advantage that the provider does not have to hold public IP addresses for its customers. Only the dial-up server must have a public IP address for the connection to the Internet. Furthermore, in this embodiment a high level of security is ensured since both subscribers of the data connection are located in a closed network segment whose access requires authentication. Access can not be established unchecked by any participant. Thus, secure and unrestricted bidirectional IP-based communication between all devices within the closed user group is possible. Another advantage of this embodiment is that it allows a data connection with any mobile device, such as a cell phone or a laptop with GSM modem card, from abroad to a mobile device in the country without expensive roaming charges. With the mobile phone, a dial-up to the Internet via GPRS or UMTS can be made abroad via a local APN via a local provider. When dialing in, the phone receives a public IP address. Under this public IP address, the mobile as "client" in the sense of the particular embodiment according to claim 4 step b. Establish an IP connection to the dial-up server of the provider and establish a bidirectional data connection to the mobile device via the authentication and the receipt of the private IP address from the private IP-based network of the provider.

In another embodiment, encrypted connections from the public IP network are permitted to increase security. For this purpose, the dial-up server can be preceded by a gateway via which an encrypted connection is established, for example a VPN tunnel (VPN = "Virtual Private Network").

• a. jedes Mobilfunkgerät über eine Authentifizierung eine Daten-Mobilfunkverbindung über einen Zugangspunkt zum Provider etabliert,
• b. den Mobilfunkgeräten durch einen IP-Server des Providers anhand der Authentifizierungsdaten feste IP-Adressen aus dem Adressraum einer geschlossenen Benutzergruppe innerhalb eines privaten IP-Netzwerksegments des Providers zugeordnet und die Zuordnung dauerhaft gespeichert werden,
• c. die Daten-Verbindung zwischen den Mobilfunkgeräten anhand der zugeordneten IP-Adressen über das private IP-Netzwerksegment des Providers gekoppelt werden, indem jeweils ein Gateway mittels Routingvorschriften eine dauerhafte bidirektionale Kommunikationsverbindung zwischen dem Mobilfunkgerät und dem privaten IP-Netzwerksegment des Providers vermittelt.

In an alternative modification of the invention, the initiative establishment of a data connection to a mobile terminal from another mobile terminal is made possible. This is achieved by a method for bidirectional data communication of mobile devices, characterized in that

• a. every mobile device establishes a data mobile connection via an access point to the provider via an authentication,
• b. assigned to the mobile devices by an IP server of the provider based on the authentication data fixed IP addresses from the address space of a closed user group within a private IP network segment of the provider and the assignment permanently stored
• c. the data connection between the mobile devices are coupled on the basis of the assigned IP addresses over the private IP network segment of the provider, by a gateway each routing means a permanent bidirectional communication connection between the mobile device and the private IP network segment of the provider.

Also by this method, the general problem according to the invention is solved, that a data connection to a mobile terminal from "outside" can not be initiated. In the above modification, this is achieved in that the data connection between mobile devices from (different) mobile networks takes place. This variant of the solution has the particular advantage that several mobile devices can also be connected to one another from different mobile networks of different providers.

The method according to the invention will be described in more detail below for illustrative purposes with reference to two exemplary embodiments:

1 shows a schematic arrangement of various components for IP-based data communication between an Internet terminal 1 and the datalogger 2 a solar system equipped with a GPRS enabled cellular modem 3 connected is. The data logger 2 has an integrated web server 4 via the GPRS modem 3 Current data of the solar system can be accessed and control functions can be performed in the solar system. The GPRS modem 3 has a SIM card 5 for physical identification of the modem in the mobile network. To establish accessibility via the Internet, the operator of the solar system selects himself with the GPRS modem 3 over the next APN of the mobile network 6 with his username "Solar 1 "And the corresponding password at the RADIUS server 7 in the network 8th of the provider and establishes a GPRS data cellular connection to the network 8th the provider. The user name indicates the IP server 9 the GPRS modem 3 the for the user name "Solar 1 "Permanently stored IP address 192.168.1.252 from the closed user group of the solar system operator, passing through a private class C subnet segment with the mask 255.255.255.252 within the private class C network segment in the network 8th the provider is formed, too. For the duration of the GPRS data cellular connection between the GPRS modem 3 and the network 8th takes over the gateway 10 bidirectional protocol translation between the GPRS protocol of the data mobile connection and the IP protocol of the private class C network segment in the network 8th the provider. To exercise monitoring and control tasks then chooses an employee of the solar system operator from his workplace at the Internet terminal 1 over the internet connection 11 his internet access provider in the network 8th of the provider. Here he gives to the RADIUS server 7 the second user name "Solar 2 "Along with the associated password, based on which the Internet terminal 1 from the IP server 9 for the user name Solar 2 Permanently stored additional IP address 192.168.1.253 is assigned from the closed user group of the solar system operator. Now is between the GPRS modem 3 and the internet terminal 1 an IP data connection through the private subnet segment with mask 255.255.255.252 within the Class C private network networked network 8th established by the provider. The employee of the solar system operator can use the Internet terminal 1 via this IP data connection with a browser on the in the data logger 2 integrated web server 4 to retrieve the current system data of the solar system and perform a system check of the solar system. The browser on the terminal 1 generated http requests are made via the IP data connection to the gateway 10 forwarded by this to the GPRS protocol, and the GPRS cellular modem 3 to the web server 4 forwarded.

2 shows a schematic arrangement of various components for IP-based data communication between the Internet server 1' a weather service, the data interface 2 ' a weather station that uses a GPRS-enabled cellular modem 3 ' connected to a GPRS-enabled mobile phone 3 ". The elements of the arrangement after 2 are as far as they are with elements of 1 in their function, indicated by the same reference numerals but with different indices. The data interface 2 ' has an integrated control server 13 via the GPRS modem 3 ' Current data of the weather station can be accessed and control and / or maintenance functions can be performed at the weather station. The GPRS modem 3 ' has a SIM card 5 ' for physical identification of the modem in the mobile network. To establish accessibility via the Internet, the operator of the weather station dials with the GPRS modem 3 ' over the next APN of the mobile network 6 ' with his username "Weather 1 "And the corresponding password at the RADIUS server 7 ' in the network 8th' of the provider and establishes a GPRS data cellular connection to the network 8th' the provider. The user name indicates the IP server 9 ' the GPRS modem 3 ' for the username "weather 1 "Permanently stored IP address 10.0.0.1 from the weather station operator's closed user group passing through a private Class A subnet segment with the mask 255.255.255.0 within the Class A private network segment on the network 8th' the provider is formed, too. For the duration of the GPRS data cellular connection between the GPRS modem 3 ' and the network 8th' takes over the gateway 10 ' bi-directional protocol translation between the GPRS protocol of the data mobile connection and the IP protocol of the private class A network segment in the network 8th' the provider. For automated retrieval of weather data selects the Internet server 1' timed via the encrypted VPN Internet connection 14 in the network 8th' of the provider.

Here he gives to the RADIUS server 7 ' the second user name "Weather 2 "Along with the associated password on the basis of which the Internet server 1' from the IP server 9 for the username "weather 2 "Permanently stored additional IP address 10.0.0.2 is assigned from the closed user group of the operator of the weather station. The VPN gateway 15 takes over the duration of the encrypted VPN Internet connection 14 between the internet server 1' and the network 8th' bidirectional decryption or encryption between the IP protocol of the Class A private network segment on the network 8th' and the encrypted VPN Internet connection 14 , Now is between the GPRS modem 3 ' and the internet server 1' an IP data connection through the private subnet segment with the mask 255.255.255.0 within the Class A private network segment on the network 8th' established by the provider. The internet server 1' can connect to the data interface via this IP data connection 2 ' integrated control server 13 automatically access and retrieve the current weather data and process it further. To carry out maintenance and control tasks, an employee of the operator of the weather station then selects his GPRS-enabled mobile telephone 3 '' out over the next APN of the mobile network 6 '' with his username "Weather 3 "And the corresponding password at the RADIUS server 7 ' in the network 8th' of the provider and establishes a GPRS data cellular connection to the network 8th' the provider. The user name indicates the IP server 9 ' the mobile phone 3 '' for the username "weather 3 "Permanently stored IP address 10.0.0.3 from the closed user group of the operator of the weather station. During the duration of the GPRS data cellular connection between the mobile phone 3 '' and the network 8th' takes over the gateway 10 ' in another instance, bidirectional protocol translation between the GPRS protocol of the data cellular connection and the IP protocol of the private class A network segment in the network 8th' the provider. Now is between the mobile phone 3 '' and the GPRS modem 3 ' an IP data connection through the private subnet segment with the mask 255.255.255.0 within the Class A private network segment on the network 8th' established by the provider. The employee of the weather station operator can use the mobile phone 3 '' via this IP data connection with a control program on the in the data interface 2 ' integrated control server 13 access and thus carry out maintenance and control work at the weather station. The from the control program on the mobile phone 3 '' generated inquiries are thereby over the data mobile connection over the portable radio net 6 '' to the gateway 10 ' from this to the IP protocol of the private class A network segment in the network 8th' implemented by the provider, then from the gateway 10 ' to the GPRS protocol of the data cellular connection over the cellular network 6 ' implemented, and by the GPRS cellular modem 3 ' to the control server 13 forwarded.

4. Brief description of the drawings:

1 shows the schematic arrangement of the data logger a solar system, a mobile device, a network of the provider and an Internet terminal for performing the communication method according to the invention.

2 shows the schematic arrangement of the data interface of a weather station, a network of the provider, the Internet server of a weather service and GPRS-enabled mobile phone for performing the communication method according to the invention.

5. Industrial Applicability:

The methods according to the invention are primarily suitable for the remote-controlled exercise of monitoring and control tasks, for example for wind power plants, solar plants or traffic control systems.

Claims (3)

Method for the integration of mobile radio devices ( 3 . 3 ' . 3 '' ) in IP-based data networks, where a. the mobile device ( 3 . 3 ' . 3 '' ) establishes a data mobile connection via an access point to the provider via an authentication, b. the mobile device ( 3 . 3 ' . 3 '' ) by an IP server ( 9 . 9 ' ) is assigned based on the authentication data a fixed IP address from the address space of its closed user group and the assignment is permanently stored, c. the data mobile connection based on the assigned IP address via a gateway ( 10 . 10 ' ) of the provider is coupled to the IP-based data network during the duration of the data mobile connection, the gateway ( 10 . 10 ' ) using routing rules a permanent bidirectional communication connection between the mobile device ( 3 . 3 ' . 3 '' ) and the IP-based data network within the address space of its closed user group, characterized in that d. that it is at the the mobile device ( 3 . 3 ' . 3 '' ) is a private IP address from a private IP network segment of the provider, e. a client ( 1 . 1' ) from an IP-based public network using password-based authentication to make an IP connection to a dial-in server ( 7 . 7 ' ) of the provider with publicly available IP address, f. the client ( 1 . 1' ) through the IP server ( 9 . 9 ' ) of the provider on the basis of the authentication data assigned to a further private IP address from the private IP network segment of the provider from the address space of the same closed user group and the assignment is permanently stored, g. the data mobile connection and the client ( 1 . 1' ) are coupled from the public IP-based network based on the associated private IP addresses over the private IP network segment of the provider. A method according to claim 1, characterized in that the authentication according to step a. via a user / password check. Method according to Claim 1 or 2, characterized in that the provider only dials encrypted connections from public IP networks for dialing in ( 14 ) via a gateway ( 15 ), over which IP connections can be transmitted tunneled.

Images